The present invention relates generally to agricultural machinery and, more particularly, to improvements to agricultural harvesting machines.
The invention further relates to a switching device for cutter blades, which are used for comminuting crop material in agricultural harvesting machines, in particular for round and square baling presses as well as self-loading forage wagons.
Switching devices of this kind for optional operation of the number of operative cutter blades for comminuting crop material are well known in various designs on agricultural harvesting machines. For example, in German patent 43 02 199 C2 is shown a cutting device having a plurality of pivotably arranged cutter blades which are brought into the cutting position by hydraulically controllable support members and released from the support members completely or in an optional number for pivoting into a non-cutting position by means of a switching device. The support members are constructed as spring-loaded push rods which, from a central location, are brought into a working position where all the cutter blades are in the cutting position. Switching of individual cutter blades, groups of cutter blades or all cutter blades to the cutting position or the non-cutting position takes place from a second location. This second location cooperates with retaining elements for the individual push rods and is formed by a rotatable switching shaft with individual control cams for each cutter blade. Each push rod is connected to a controllable locking and unlocking rod for release and retention of the push rod and for switching the cutter blades to the cutting position or the non-cutting position. This known switching device fulfills the necessary functional conditions for the actuation of the cutter blades at any given time, but requires relatively high production and maintenance costs.